Need to add 'python-MySQLdb' in requirements list for Murano API service

[Timur Nurlygayanov]

Need to add MySQLdb library in requirements list for Murano API service (this library will be used for mySQL connections to Murano database)

There is the following requirements list now there:
{code}
pbr>=0.5.21,<1.0
Babel>=1.3
SQLAlchemy>=0.7.8,<=0.7.99
anyjson>=0.3.3
eventlet>=0.13.0
PasteDeploy>=1.5.0
Routes>=1.12.3
WebOb>=1.2.3,<1.3
wsgiref>=0.1.2
argparse
sqlalchemy-migrate>=0.7.2
httplib2
kombu>=2.4.8
pycrypto>=2.6
iso8601>=0.1.4
six>=1.4.1
netaddr

# Note you will need gcc buildtools installed and must
# have installed libxml headers for lxml to be successfully
# installed using pip, therefore you will need to install the
# libxml2-dev and libxslt-dev Ubuntu packages.
lxml>=2.3

# For paste.util.template used in keystone.common.template
Paste

passlib
jsonschema>=1.3.0,!=1.4.0
python-keystoneclient>=0.3.2
oslo.config>=1.2.0
murano-common>=0.2.11

{code}